Photochemical acylations of 2-substituted-1,4-naphthoquinones with various aldehydes furnished acylated hydroquinones and acylated quinones in moderate to good combined yields. All reactions are easily performed and open a rapid access to biologically active compounds. For the 2-methyl-1,4-naphthoquinone/butyraldehyde pair, a novel tri-keto compound has been additionally isolated. (c) 2005 Elsevier Ltd. All rights reserved.